: "All shall love me and despair." Galadriel choosing to remain Galadriel - given the part that she played in the rebellion of the Noldor in the first age, her love of Middle Earth and the certainty that Lorien would diminish with the destruction of the ruling ring. Her refusal of Frodo's gift was surely the most selfless of acts.

: Theoden riding unto great reknown on the Fields of the Pellenor. Gives me a shiver every time I read his elegy.

: Bilbo handing over the ring. The only one ever to do so freely (apart from Sam who really hadn't had it long enough to have much of an effect).

: Dain at the Iron Hills defending the body of Brand. Wasn't this the same Dain that slew Azog at Nandhurion? What a warrior!

: Farmer Maggot vs the Nazgul.

: Barleyman Butterbur facing up to Gandalf after nearly blowing the whole thing. I would have been hiding in the cellar.

: The last stand outside the gates of Mordor. Doomed, doomed, doomed.

: What about the most heroic acts of the whole mythos? For my part.

: The crossing of the Hexarxe
: Fingolfin vs. Morgoth
: Beren and Luthien
: Hurin - his whole life was a trial
: Earendil
: Galadriel fighting the long defeat

: Doh run out of time - back to work

I believe that the greatest of all acts of heroism was the last stand of the men of Dor-Lomin, They were not Fey like Fingolfin, they just stood and fought in the greatest display of courage, and they died to a man. Apart of course from Hurin (have you noticed that Gothmog, who had a habit of killing Elf-lords, stood by and let his guard sate Hurin's axe's bloodthirst? did he not want to engage the mightiest mortal warrior??), who then made yet another extreme act of courage by mocking Morgoth himself- who else dared that??, and enduring the next 28 years while his kin withered under the curse. However, Morwën, Nienor and turin showed extreme endurance and courage as well by acomplishing what they did in the face of that curse.
What about Arwën choosing mortality for her love?
I will join in applauding Galadriel and Bilbo for courage, losing your life is one thing, on which you must reckon in Endor, but resisting the temptation of The One!! or the crushing will of the Ainur, which includes Frodo v. Sauron and Hurin v. Morgoth Bauglir.